This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This is a clinical study will test the hypothesis that PD patients experience accelerated brain atrophy distinct from the normal aging process in healthy controls as shown in lateral ventricular enlargement and volume loss in targeted basal ganglia structures. Data from this study might help to better understand the disease progression and perhaps correlate symptom progression with changes in structural MRI and evaluations of mood, memory and sleepiness. Plans are to screen 164 people with the goal of recruiting 134 subjects (54 controls and 80 PD patients).